Cadillac: Cooling fans, engine cooling system, fuse panel

Question
QUESTION: I have a 1996 Cadillac DeVille. My problem is that the air compressor will not kick in and the engine cooling system fans will not work. The fans DID work when the a/c was on, only, but now neither the fans or the a/c work.

ANSWER: IS or HAS the check engine light illuminated on the dash and or have you seen any messages on the message display panel ?.

Does the engine overheat ?.

---------- FOLLOW-UP ----------

QUESTION: No....no messages on the display panel.
The motor overheats if car is not moving. Checked all fuses and changed the compressor relay in the fuse panel.

Answer
Check the computer for fault CODES.

1. Ignition ON. Engine OFF.

2. Simultaneously push and hold the OFF and WARMER (^) buttons on the climate control panel for 3 seconds and release the buttons.

3. Look at the fuel data display and tell me EVERYTHING you see as if you were video taping it.

4. When the display stops at PCM?. shut OFF ignition.